but import statement imports it only once and i have no clues how to fix it.
Second problem is that when if i want to continue counting i need to restart the program all over again i tried something like this

Look at this here two way to work with function.
Maybe you get some idèe on how to solve your +*-/ with function and a menu.
One function i just return and do calulation in main.
They other function all calulation and exception handling is done in fuction.

Try to get comfortable with use off function.
Then look at classes and a more OOP apropose to solve problem. except: is the easy way here a catch many errors.
You can catch error you need.
Try option 1 the one without exception handling and type a letter.
Now you get a NameError
To catch that except NameError: Just a litte on how to handle error.

You should not write except: clauses without targeting a specific exeption. For example if you're reading user input and you're expecting a number and the user types "hello", then float("hello") will raise a ValueError. You can catch it with except ValueError .
There are many good reasons not to use except: alone. One of them is that when there is a bug in a python program, python will raise an unexpected exception. This exception will not be caught and you will have a nice tracebak in the output, which tells you where is your error. If you catch all exceptions, you will not see the traceback, and you will waste time finding the bug. In python, NOT catching exceptions is a powerful debugging tool. There are other reasons too.

well i don't like the format how you enter numbers.
the way i want it to be is like you type in first number then you type in the command then you type in 2nd number
i mean if i would chose method you offer first i chose what i want to do e.g add divide etc. and then i type in numbers it makes no sense :)

Hi. so this is actually a continuation from another question of mine[Here](https://www.daniweb.com/programming/software-development/threads/506795/dynamically-add-values-into-datagridview-cell-from-listbox-vb2010) but i was advised to start a new thread as the original question …

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